Tag: AJ26 engine

Orbital Sciences Corporation Antares rocket and Cygnus spacecraft blasts off on July 13 2014 from Launch Pad 0A at NASA Wallops Flight Facility , VA, on the Orb-2 mission and loaded with over 3000 pounds of science experiments and supplies for the crew aboard the International Space Station. Credit: Ken Kremer – kenkremer.com

NASA and Orbital ATK announced that the re-engined Antares will launch during a five-day launch window that opens no earlier than October 9-13, 2016 on the OA-5 Cygnus cargo mission from the Mid-Atlantic Regional Spaceport at NASA’s Wallops Flight Facility on Virginia’s picturesque Eastern shore.

“A more specific date will be identified upon completion of final operational milestones and technical reviews,” according to statements from NASA and Orbital ATK.

If Antares launches on Oct. 9, liftoff is set 10:47 p.m. EDT and becomes progressively earlier on succeeding days. The launch time moves up to 9:13 p.m. EDT on Oct. 13.

If the launch takes place during this window, it will mark the first truly nighttime launch for Antares from Virgina.

“The arrival and berthing of Cygnus to the International Space Station will be determined by the exact launch date and in coordination with other space station activities,” says NASA.

The Cygnus cargo spacecraft was moved this week from the NASA Wallops payload processing facility to the spacecraft fueling facility on Wallops Island.

The next step is to integrate Cygnus onto the Orbital ATK Antares 230 rocket inside the HIF (Horizontal Integration Facility) in anticipation of the launch slated for no earlier than Oct. 9 at 10:47 p.m. EDT.

The Antares 230 medium-class commercial launch vehicle rocket has been upgraded with new first stage Russian-built RD-181 engines fueled by LOX/kerosene – that had to be fully validated before launching NASA’s precious cargo to the International Space Station (ISS).

For the OA-5 mission, the Cygnus advanced maneuvering spacecraft will be loaded with approximately 2,400 kg (5,290 lbs.) of supplies and science experiments for the International Space Station (ISS).

Under the Commercial Resupply Services (CRS) contract with NASA, Orbital ATK will deliver approximately 28,700 kilograms of cargo to the space station. OA-5 is the sixth of these missions.

Orbital ATK’s Antares commercial rocket had to be overhauled with completely new first stage engines following the catastrophic launch failure nearly two years ago on October 28, 2018 just seconds after blastoff that doomed the Orb-3 resupply mission to the space station.

The goal of the Antares ‘Return to Flight’ mission is to launch Orbital ATK’s Cygnus cargo freighter on the OA-5 resupply mission for NASA to the ISS and restore the Antares rocket to flight status.

To that end the aerospace firm completed a successful 30 second long test firing of the re-engined first stage on May 31 at Virginia Space’s Mid-Atlantic Regional Spaceport (MARS) Launch Pad 0A – as I reported here earlier.

First stage of Orbital ATK Antares rocket outfitted with new RD-181 engines stands erect at Launch Pad-0A on NASA Wallops Flight Facility on May 24, 2016 in preparation for the upcoming May 31 hot fire engine test. Credit: Ken Kremer/kenkremer.com

Teams from Orbital ATK and NASA have been scrutinizing the data in great detail ever since then to ensure the rocket is really ready before committing to the high stakes launch.

“Orbital ATK completed a stage test at the end of May and final data review has confirmed the test was successful, clearing the way for the Antares return to flight,” said the company.

“Simultaneously, the company has been conducting final integration and check out of the flight vehicle that will launch the OA-5 mission to ensure that all technical, quality and safety standards are met or exceeded.”

Soviet era NK-33 engines refurbished as the AJ26 exactly like pictured here probably caused Antares’ rocket failure on Oct. 28, 2014. Orbital Sciences technicians at work on two AJ26 first stage engines at the base of an Antares rocket during exclusive visit by Ken Kremer/Universe Today at NASA Wallaps. These engines powered the successful Antares liftoff on Jan. 9, 2014 at NASA Wallops, Virginia bound for the ISS. Credit: Ken Kremer – kenkremer.com

The RD-181 replaces the previously used AJ26 engines which failed moments after liftoff during the last launch on Oct. 28, 2014 resulting in a catastrophic loss of the rocket and Cygnus cargo freighter.

The RD-181 flight engines are built by Energomash in Russia and had to be successfully tested via the static hot fire test to ensure their readiness.

WALLOPS ISLAND, VA – The soon to be reborn Orbital ATK Antares commercial rocket sporting new first stage engines has been raised at its repaired launch pad on Virginia’s scenic eastern shore for a long awaited test firing of the powerplants. The static test firing is now slated to take place in less than 3 days on Tuesday evening, May 31.

The engine test will be conducted using only the first stage of Antares at the Mid-Atlantic Regional Spaceport’s Pad-0A at NASA’s Wallops Flight Facility.

The raised rocket with the first stage capped at the top is visible right now at the Wallops pad – as seen in my new photos taken this week.

NASA announced that the static test firing is slated for no earlier than May 31 during a test window that runs from 5 p.m. to 8:15 p.m. EDT. As a contingency, the Wallops range has been reserved for backup test dates that run through June 5 just in case issues crop up.

NASA will not be carrying a live webcast of the test. Rather they will note the completion of the test on the Wallops’ Facebook and Twitter sites.

Orbital ATK’s Antares first stage with the new RD-181 engines stands erect at Virginia Space’s Mid-Atlantic Regional Spaceport Pad-0A on NASA Wallops Flight Facility on May 24, 2016 in preparation for the upcoming stage test on May 31. Credit: Ken Kremer/kenkremer.com

The test firing will be visible from various public viewing locations in the local Wallops area. However the NASA Wallops Visitor center will not be open.

NASA will not be carrying a live webcast of the test. Rather they will note the completion of the test on the Wallops’ Facebook and Twitter sites.

The test firing will be visible from various public viewing locations in the local Wallops area. However the NASA Wallops Visitor center will not be open.

Orbital ATK’s Antares first stage with the new RD-181 engines stands erect at Virginia Space’s Mid-Atlantic Regional Spaceport Pad-0A on NASA Wallops Flight Facility on May 24, 2016 in preparation for the upcoming stage test on May 31. Credit: Ken Kremer/kenkremer.com

The test involves firing up Antares dual first stage RD-181 engines at full 100% power (thrust) for a scheduled duration of approximately 30 seconds. Hold down restraints will keep the rocket firmly anchored at the pad during the test.

The new RD-181 engines are installed on the Orbital ATK Antares first stage core ready to support a full power hot fire test at the NASA Wallops Island launch pad in May 2016. New thrust adapter structures, actuators, and propellant feed lines are incorporated between the engines and core stage. Credit: Ken Kremer/kenkremer.com

A successful outcome is absolutely crucial for permitting Antares to carry out its ‘Return to Flight’ launch dubbed OA-5 and set for sometime this summer.

“The hot fire will demonstrate the readiness of the rocket’s first stage and the launch pad fueling systems to support upcoming flights,” said NASA officials.

Antares launches ground to a halt following a devastating launch failure 19 months ago which destroyed the rocket and its payload of space station science and supplies for NASA in a huge fireball.

The ‘Return to Flight’ blastoff – which could come as soon as July 2016 – will be the first for the private Antares rocket since that catastrophic launch failure on Oct. 28, 2014, just seconds after liftoff from Wallops. That flight was carrying Orbital ATK’s Cygnus cargo freighter on the critical Orb-3 resupply mission for NASA and the astronauts living and working on the International Space Station (ISS).

The launch mishap was traced to a failure in the AJ26 first stage engine turbopump and caused Antares launches to immediately grind to a halt.

The RD-181 replaces the AJ26. The flight engines are built by Energomash in Russia.

“They are a good drop in replacement for the AJ26. And they offer 13% higher thrust compared to the AJ26,” said Kurt Eberly, Orbital ATK Antares deputy program manager, in an interview with Universe Today.

As a result of switching to the new RD-181 engines, the first stage also had to be modified to incorporate new thrust adapter structures, actuators, and propellant feed lines between the engines and core stage structure.

“After the 30 second test is done we will shut it down and have a pile of data to look at,” Eberly told Universe Today.

“Hopefully it will confirm all our environments and all our models and give us the confidence so we can proceed with the return to flight.”

Technicians have been processing the rocket at the pad to ready it for the test. They also conducted a wet dress rehearsal (WDR) and loaded the propellants like during an actual launch campaign.

The full up engine test follows the WDR.

“After the WDR we will do the stage test,” Eberly explained.

“It is a 30 second test. We will fire up both engines and hit all 3 power levels that we plan to use in flight.”

“We will use the thrust vector controls. So we will move the nozzles and sweep them through sinusoidal sweeps at different frequencies and excite various resonances and look for any adverse interaction between fluid modes and structural modes.”

The test uses the first stage core planned to launch the OA-7 mission from Wallops late this year.

The new RD-181 engines are installed on the Orbital ATK Antares first stage core ready to support a full power hot fire test at the NASA Wallops Island launch pad in May 2016. Credit: Ken Kremer/kenkremer.com

After the engine test is completed, the stage will be rolled back to the HIF and a new stage fully integrated with the Cygnus cargo freighter will be rolled out to the pad for the OA-5 ‘Return to Flight’ mission as soon as July.

“Orbital ATK is building, testing and flying the Antares rocket and Cygnus cargo spacecraft under NASA’s Commercial Resupply Services contract. NASA initiatives like the cargo resupply contracts are helping develop a robust U.S. commercial space transportation industry with the goal of achieving safe, reliable and cost-effective transportation to and from the International Space Station and low-Earth orbit,” according to NASA.

Orbital ATK’s Antares first stage with the new engines is rolled from NASA Wallops Flight Facility’s Horizontal Integration Facility to Virginia Space’s Mid-Atlantic Regional Spaceport Pad-0A on May 12, 2016, in preparation for the upcoming stage test in the next few weeks. Credit: NASA’s Wallops Flight Facility/Allison Stancil

An upgraded version of Orbital ATK’s commercially developed Antares rocket has at last rolled out to its launch pad on the Virginia shore – thus paving the path for a high stakes first stage engine test looming “in the next few weeks,” according to the aerospace firm.

Orbital ATK hopes to restart resupply missions to the crews living aboard the space station as soon as July – less than two months from today.

The now revamped launch vehicle dubbed Antares 230 has been re-engined and upgraded with a pair of modern new first stage engines, the Russian-built RD-181 fueled by LOX/kerosene.

The new RD-181 engines are installed on the Orbital ATK Antares first stage core ready to support a full power hot fire test at the NASA Wallops Island launch pad in May 2016. Credit: Ken Kremer/kenkremer.com

To prepare for the upcoming stage test, workers carefully assembled and thoroughly tested an Antares first stage equipped with the new RD-181 engines.

On May 12, 2016, they moved the vehicle on a dedicated multi-wheeled transporter from the Horizontal Integration Facility at NASA’s Wallops Flight Facility to Virginia Space’s Mid-Atlantic Regional Spaceport Pad-0A about a mile away.

Orbital ATK’s Antares first stage with the new engines is rolled from NASA Wallops Flight Facility’s Horizontal Integration Facility to Virginia Space’s Mid-Atlantic Regional Spaceport Pad-0A on May 12, 2016, in preparation for the upcoming stage test in the next few weeks. Credit: Orbital ATK

The team has about 3 weeks of check out work to complete before the live firing, including a wet dress rehearsal (WDR).

“The team will continue to work meticulously as they begin final integration and check outs on the pad and several readiness reviews prior to the test. The window for the stage test will be over multiple days to ensure technical and weather conditions are acceptable,” noted Orbital ATK in a statement.

The ‘Return to Flight’ blastoff – currently planned for as soon as July 2016 – will be the first for the private Antares rocket since a catastrophic launch failureon Oct. 28, 2014, just seconds after liftoff from Wallops. That flight was carrying Orbital ATK’s Cygnus cargo freighter on the critical Orb-3 resupply mission for NASA to the space station.

The launch mishap was traced to a failure in the AJ26 first stage engine turbopump and caused Antares launches to immediately grind to a halt.

They sought a replacement and eventually decided to upgrade Antares by powering it with a pair of new Russian-made RD-181 main stage engines and modifying the first stage core structure to accommodate the new engines.

The RD-181 flight engines are built by Energomash in Russia.

“They are a good drop in replacement for the AJ26. And they offer 13% higher thrust compared to the AJ26,” Eberly noted.

As a result of switching to the new RD-181 engines, the first stage also had to be modified to incorporate new thrust adapter structures, actuators, and propellant feed lines between the engines and core stage structure.

Independent review teams have also been brought in to ensure that no stone is left unturned and everything is being done to achieve success.

The new RD-181 engines are installed on the Orbital ATK Antares first stage core ready to support a full power hot fire test at the NASA Wallops Island launch pad in May 2016. New thrust adapter structures, actuators, and propellant feed lines are incorporated between the engines and core stage. Credit: Ken Kremer/kenkremer.com

Now it’s time for the real deal. After all the hard work Antares is now at the pad.

“We place it on the pad about 3 weeks prior to the engine test,” Eberly told me. “Then we and do a series of integrated checks, and electrical checks and pressure checks on the feed lines.”

“Then we will do a wet dress rehearsal where we will load the tanks with propellants. We will load the pressure bottles, pressurize the tanks and then count down just like we would for the real stage test. And right before we ignite the engines we will call a halt to the sequencer.”

“Then we will detank and pick through all that data and do a readiness review.”

If the WDR goes well, the full up engine test will follow.

“Then we will do the stage test,” Eberly explained.

“It is a 30 second test. We will fire up both engines and hit all 3 power levels that we plan to use in flight.”

“We will use the thrust vector controls. So we will move the nozzles and sweep them through sinusoidal sweeps at different frequencies and excite various resonances and look for any adverse interaction between fluid modes and structural modes.”

The vehicle and pad will be outfitted with lots of special instrumentation to gather as much test data as possible.

“We will have a lot of accelerometers and extra instrumentation and extra microphones on the test article and around the pad.

“After the 30 second test is done we will shut it down and have a pile of data to look at.”

“That will hopefully confirm all our environments and all our models and give us the confidence so we can proceed with the return to flight on the OA-5 mission.”

The test uses the first stage core planned to launch the OA-7 mission late this year.

After the engine test is completed, the stage will be rolled back to the HIF and a new stage fully integrated with the Cygnus will be rolled out to the pad for the OA-5 ‘Return to Flight’ mission as soon as July.

In the past 6 months, Orbital ATK has successfully resumed launches of their Cygnus cargo freighters to the ISS – as an interim measure until Antares is returned to flight status

A Cygnus cargo spacecraft named the SS Rick Husband is being prepared inside the Payload Hazardous Servicing Facility at NASA’s Kennedy Space Center for upcoming Orbital ATK CRS-6/OA-6 mission to deliver hardware and supplies to the International Space Station. The Cygnus is scheduled to lift off atop a United Launch Alliance Atlas V rocket on March 22, 2016. Credit: Ken Kremer/kenkremer.com

NASA WALLOPS FLIGHT FACILITY, VA – Assembly and testing of a significantly upgraded version of Orbital ATK’s commercially developed Antares rocket has kicked into high gear and is on target for rebirth – as the clock ticks down towards its ‘Return to Flight’ by approximately mid-2016 from a launch pad at the Mid-Atlantic Regional Spaceport (MARS) in Virginia, company managers told Universe Today during a recent up close media visit to see the actual flight hardware.

Cygnus service module built by Orbital ATK in their Dulles, Virginia cleanroom is shown here with unfurled UltraFlex solar panels that will fly for the first time with mated pressurized module on the OA-4 ISS resupply mission on ULA Atlas V rocket on Dec. 3, 2015 from Cape Canaveral, Florida. Credit: Orbital ATK
See OA-4 mission patch and hardware photos below

The March 2016 launch date of Antares from the Wallops Island base along Virginia’s eastern shore was announced by David Thompson, Orbital ATK, President and CEO, during a recent conference call with investors and analysts regarding the formal merger of Orbital Sciences and ATK.

“The target date for that [Antares launch] is the 1st of March next year,” said Thompson.

Cygnus will be fully loaded with new supplies for the station crew.

“The first launch … will have a full cargo load on board.”

The Orbital Sciences Corp. commercial Antares rocket was destroyed in a raging inferno about 15 seconds after liftoff on Oct. 28 when one of the Soviet-era built first stage engines apparently exploded and cascaded into a spectacular aerial fireball just above the launch pad 0A at NASA’s Wallops Flight Facility on the doomed Orb-3 mission carrying the Cygnus resupply module to the International Space Station (ISS).

Orbital’s privately developed Cygnus pressurized cargo freighter was loaded with nearly 5000 pounds (2200 kg) of science experiments, research instruments, crew provisions, spare parts, spacewalk and computer equipment and gear on the Orb-3 mission. The module and all its contents were destroyed.

Orbital established an independent accident investigation review board immediately following the launch failure.

“We are about four months now into the recovery from the failure,’ said Thompson.

“The next Cygnus will be launched on the upgraded Antares from Wallops Island. The target date for that is the 1st of March next year.”

After the launch failure Orbital, decided to ditch the trouble plagued AJ-26 and “re-engineered” the vehicle with new engines.

The Antares first stage had been powered by a pair of the aging AJ26 engines. These will now be replaced by a pair of newly manufactured Russian RD-181 engines, assembled and purchased from NPO Energomash.

“The first launch of the re-engineered vehicle in March of next year … will have a full cargo load on board.”

Thompson said the March 2016 launch target date will be preceded by a hot fire test of the first stage engines, which is currently planned to take place in January 2015. They will not conduct a demonstration launch and have opted for a full up space station resupply flight.

“We’re going to go with the cargo load on the first launch. What we are going to do in advance of that, in January of next year, is we’re going to take the first stage of Antares out to the launch pad with the new engines and do a flight readiness firing, somewhat similar to what we did back in early 2013, in advance of the first Antares flight,” said Thompson.

“But other than that, unless something came up there that was surprising, we should then be able to proceed pretty expeditiously to the first launch of the re-engineered vehicle in March of next year, and that will have a full cargo load on board.”

Orbital Sciences technicians at work on two AJ26 first stage engines at the base of an Antares rocket during exclusive visit by Ken Kremer/Universe Today at NASA Wallaps. These engines powered the successful Antares liftoff on Jan. 9, 2014 at NASA Wallops, Virginia bound for the ISS. Credit: Ken Kremer – kenkremer.com

Thompson also reiterated that Orbital will fully meet its resupply services contarct with NASA and make up for the lost cargo.

The Orbital-3, or Orb-3, mission that ended in disaster on Oct 28, was to be the third of eight cargo resupply missions to the ISS through 2016 under the NASA Commercial Resupply Services (CRS) contract award valued at $1.9 Billion. Under the CRS program Orbital is to deliver 20,000 kilograms of research experiments, crew provisions, spare parts, and hardware for the eight ISS flights.

“The focus all along has been to do everything we can to fulfill our commitments to delivering cargo to the space station for NASA, and to minimize any disruption that we can to the delivery schedules.”

Towards that end Orbital ATK has contracted with United Launch Alliance (ULA) to launch at least one and up to two Cygnus cargo missions to the International Space Station (ISS) under NASA’s Commercial Resupply Services (CRS) program.

The first Cygnus mission would liftoff sometime late in the fourth quarter of 2015 aboard an Atlas V 401 vehicle from Space Launch Complex 41 (SLC-41) at Cape Canaveral Air Force Station in Florida.

I watched the unfolding disaster first hand from the media viewing site about 1.8 miles away and filed eyewitness reports at the time. Several of my launch pad remote cameras were set up at the pad. They were impounded and the images were used by investigators during the initial investigation. They were returned to me about a month later and are featured here and in my earlier Antares reports.

In the wake of last weeks disastrous failure of the Orbital Sciences commercial Antares rocket seconds after blastoff from NASA’s Wallops Flight Facility, VA, on a critical resupply mission to the space station, Orbital’s Chairman announced a comprehensive way forward involving a two pronged strategy to quickly fulfill their cargo commitments to NASA as well as upgrade the rockets’ first stage propulsion system.

“Orbital announced comprehensive plans to fulfill its contract commitments under NASA’s Commercial Resupply Services (CRS) program as well as to accelerate an upgrade of the Antares medium-class launcher’s main propulsion system, the company said in a statement and discussion by David Thompson, Orbital’s Chairman and Chief Executive Officer, during an investors conference call.

“Orbital is taking decisive action to fulfill our commitments to NASA in support of safe and productive operations of the Space Station,” said Thompson.

“While last week’s Antares failure was very disappointing to all of us, the company is already implementing a contingency plan to overcome this setback. We intend to move forward safely but also expeditiously to put our CRS cargo program back on track and to accelerate the introduction of our upgraded Antares rocket.”

The Orbital Sciences privately developed Antares rocket was doomed by a sudden mid-air explosion some 15 seconds after liftoff from NASA’s Wallops Flight Facility, VA, at 6:22 p.m. EDT on Tuesday, October 28.

A turbopump failure in one of the rockets two Aerojet Rocketdyne AJ26 engines that power the first stage has been identified by Orbital’s Accident Investigation Board (AIB) as the probable cause of the huge explosion that destroyed the booster and its NASA payload in a raging fireball after liftoff.

Soviet era NK-33 engines refurbished as the AJ26 exactly like pictured here probably caused Antares rocket failure on Oct. 28, 2014. Orbital Sciences technicians at work on two AJ26 first stage engines at the base of an Antares rocket during exclusive visit by Ken Kremer/Universe Today at NASA Wallaps. These engines powered the successful Antares liftoff on Jan. 9, 2014 at NASA Wallops, Virginia bound for the ISS. Credit: Ken Kremer – kenkremer.com

The AJ26 engines were originally manufactured some 40 years ago in the then Soviet Union as the NK-33. They were refurbished and “Americanized” by Aerojet Rocketdyne.

“While still preliminary and subject to change, current evidence strongly suggests that one of the two AJ26 main engines that powered Antares first stage failed about 15 seconds after ignition. At this time, we believe the failure likely originated in or directly affected the turbopump machinery of this engine, but I want to stress that more analysis will be required to confirm that this finding is correct,” said Thompson.

Overall this was the 5th Antares launch using the AJ26 engines.

AJ26 engine failure was immediately suspected, though by no means certain, based on an inspection of numerous photos and videos from myself and many others that clearly showed a violent explosion emanating from the base of the two stage rocket.

The remainder of the first stage and Antares entire upper stage was clearly intact at the moment of the explosion in all the imagery.

Thompson said Orbital is accelerating contingency planning and is looking at several alternate rocket suppliers in the US and Europe to launch Orbital’s Cygnus cargo freighter to the station.

Cygnus has functioned perfectly to date and was designed to launch on other vehicles.

“Orbital will employ the inherent flexibility of our Cygnus cargo spacecraft that permits it to be launched on third party launch vehicles and to accommodate heavier cargo loads as allowed by more capable launchers. This option had already been contemplated in previous contingency plans and product improvement roadmaps and its implementation should be relatively straightforward.”

Thompson furthermore stated that the company would need to launch one or two Cygnus spacecraft on alternate providers and hope to do so during 2015 so as to keep their CRS resupply commitments to NASA on track and with minimal delay.

The next Antares/Cygnus launch from Wallops had been scheduled for no earlier than April 2015.

The April launch had been scheduled to introduce the enhanced, longer Cygnus with the capability to carry a significantly heavier cargo load to the ISS.

By employing the enhanced Cygnus, Orbital hopes to fulfill its entire CRS contract cargo up mass commitment to NASA in four flights instead of five by the end of 2016.

“Taking advantage of the spacecraft’s flexibility, we will purchase one or two non-Antares launch vehicles for Cygnus flights in 2015 and possibly in early 2016 and combine them with several upgraded Antares rocket launches of additional Cygnus spacecraft in 2016 to deliver all remaining CRS cargo,” said Thompson.

“By consolidating the cargo of five previously-planned CRS missions into four more capable ones, we believe we can maintain a similar or perhaps even a somewhat better delivery schedule than we were on before last week’s launch failure, completing all current CRS program cargo deliveries by the end of 2016.”

The possible launch providers include a United Launch Alliance Atlas V, a SpaceX Falcon 9 or a rocket from the European Space Agency at the Guiana Space Center.

Orbital had previously announced and managers told Universe Today that the company already had decided on plans to integrate a new first stage engine in a new and upgraded second generation version of Antares.

But no one at Orbital will confirm the identity of the chosen first stage engines.

“We will accelerate the introduction of Antares’ upgraded propulsion system, advancing its initial launch date from the previously planned 2017 into 2016,” said Thompson.

Thompson also said the AJ26 engine are unlikely to be used again without complete assurances.

“Consequently, we will likely discontinue the use of the AJ26 rocket engines that had been used on the first five Antares vehicles unless and until those engines can be conclusively shown to be flight worthy,” Thompson stated.

See my exclusive photos herein showing the AJ26 engines with their original NK-33 stencil, during prelaunch processing and mating to the first stage inside Orbital’s Horizontal Integration Facility (HIF) at NASA Wallops.

The NK-33 was originally designed and manufactured in the 1960s by the Kuznetsov Design Bureau for the Soviet Union’s planned N1 rocket to propel cosmonauts to the moon during the space race with NASA’s hugely successful Apollo Moon Landing program.

The 14 story Antares rocket is a two stage vehicle.

The liquid fueled first stage is filled with about 550,000 pounds (250,000 kg) of Liquid Oxygen and Refined Petroleum (LOX/RP) and powered by a pair of AJ26 engines that generate a combined 734,000 pounds (3,265kN) of sea level thrust.

The Oct. 28 launch disaster was just the latest in a string of serious problems with the AJ-26/NK-33 engines.

Earlier this year an AJ26 engine failed and exploded during pre launch acceptance testing on a test stand on May 22, 2014 at NASA’s Stennis Space Center in Mississippi.

Besides completely destroying the AJ26 engine, the explosion during engine testing also severely damaged the Stennis test stand. It has taken months of hard work to rebuild and restore the test stand and place it back into service.

The doomed mission was bound for the International Space Station (ISS) on a flight to bring up some 5000 pounds of (2200 kg) of science experiments, research instruments, crew provisions, spare parts, spacewalk and computer equipment and gear on a critical resupply mission in the Cygnus resupply ship bound for the International Space Station (ISS).

The Orbital-3, or Orb-3, mission was to be the third of eight cargo resupply missions to the ISS through 2016 under the NASA Commercial Resupply Services (CRS) contract award valued at $1.9 Billion.

Orbital Sciences is under contract to deliver 20,000 kilograms of research experiments, crew provisions, spare parts and hardware for the eight ISS flights.

I was an eyewitness to the awful devastation suffered by the Orb-3 mission from the press viewing site at NASA Wallops located at a distance of about 1.8 miles away from the launch complex.

I was interviewed by NBC News and you can watch the entire story and see my Antares explosion photos featured at NBC Nightly News on Oct. 29 here.

Watch the Antares launch disaster unfold into a raging inferno in this dramatic sequence of my photos shot on site – here.

NASA WALLOPS FLIGHT FACILITY, VA – Investigators probing last week’s catastrophic failure of an Antares commercial rocket moments after liftoff, are pointing the finger at the rocket’s Soviet-era built engines as the probable cause of the huge explosion that destroyed the booster and its NASA payload in a raging fireball after liftoff from NASA’s Wallops Flight Facility, VA, according to Orbital Sciences managers.

The Orbital Sciences privately developed Antares rocket was doomed by a sudden mid-air explosion some 15 seconds after liftoff from NASA’s Wallops Flight Facility, VA, at 6:22 p.m. EDT on Tuesday, October 28.

Antares’ first stage is powered by a pair of refurbished Aerojet Rocketdyne AJ26 engines originally manufactured some 40 years ago in the then Soviet Union and originally designated as the NK-33. Overall this was the 5th Antares launch using the AJ26 engines.

See my exclusive photos above and below showing the AJ26 engines with their original NK-33 stencil, during prelaunch processing and mating to the first stage inside Orbital’s Horizontal Integration Facility (HIF) at NASA Wallops.

The NK-33 was originally designed and manufactured in the 1960s by the Kuznetsov Design Bureau for the Soviet Union’s planned N1 rocket to propel cosmonauts to the moon during the space race with NASA’s hugely successful Apollo Moon Landing program.

Rocket developer Orbital Sciences Corp. said today, Nov. 5, that the launch mishap was probably due to “a failure in one of the two Aerojet Rocketdyne AJ26 stage one main engines.”

Engineers assisting Orbital’s Accident Investigation Board (AIB) say that failure in the AJ26 turbopump is the likely cause. The AIB is chaired by David Steffy, Chief Engineer of Orbital’s Advanced Programs Group.

“While the work of the AIB continues, preliminary evidence and analysis conducted to date points to a probable turbopump-related failure in one of the two Aerojet Rocketdyne AJ26 stage one main engines,” Orbital said in a statement.

“As a result, the use of these engines for the Antares vehicle likely will be discontinued,” said Orbital.

“We will likely discontinue the use of AJ26 rocket engines that had been used on the first five Antares launch vehicles unless and until those engines can be conclusively shown to be flight worthy,” noted David Thompson, Orbital’s Chairman and Chief Executive Officer, during an investor conference call.

Orbital’s options for the way forward will be outlined in a separate story.

Side view of two AJ26 first stage engines at the base of an Antares rocket during exclusive visit by Ken Kremer/Universe Today. These engines powered the successful Antares liftoff on Jan. 9, 2014, at NASA Wallops, Virginia. Credit: Ken Kremer – kenkremer.com

The Oct. 28 launch disaster was just the latest in a string of serious problems with the AJ-26/NK-33 engines.

Earlier this year an AJ26 engine failed and exploded during pre launch acceptance testing on a test stand on May 22, 2014, at NASA’s Stennis Space Center in Mississippi.

Besides completely destroying the AJ26 engine, the explosion during engine testing also severely damaged the Stennis test stand. It has taken months of hard work to rebuild and restore the test stand and place it back into service.

An extensive engine analysis, recheck and test stand firings by Aerojet Rocketdyne and Orbital Sciences engineers was conducted to clear this new pair of engines for flight.

Aerojet Rocketdyne purchased approximately 40 NK-33 engines in the mid-1990s and ‘Americanized’ them with multiple modifications including a gimbal steering mechanism.

AJ26 engine failure was immediately suspected, though by no means certain, based on an inspection of numerous photos and videos from myself and many others that clearly showed a violent explosion emanating from the base of the two stage rocket.

Up close view of two AJ26 first stage engines at the base of an Antares rocket during exclusive visit by Universe Today. These engines powered the successful Antares liftoff on Jan. 9, 2014, at NASA Wallops, Virginia. Credit: Ken Kremer – kenkremer.com

The remainder of the first stage and Antares entire upper stage was clearly intact at the moment of the explosion in all the imagery.

Antares was carrying the unmanned Cygnus cargo freighter on a mission dubbed Orb-3 to resupply the six person crew living aboard the International Space Station (ISS) with science experiments and needed equipment.

The AIB is making rapid progress in assessing the accident’s cause based on an analysis of the rocket’s telemetry as well as the substantial amounts of debris collected from the rocket and the Cygnus cargo freighter at the Wallops launch site.

A preliminary review of telemetry and video data has been conducted and substantial debris from the Antares rocket and its Cygnus payload has been collected and examined.

The liquid fueled first stage is filled with about 550,000 pounds (250,000 kg) of Liquid Oxygen and Refined Petroleum (LOX/RP) and powered by a pair of AJ26 engines that generate a combined 734,000 pounds (3,265kN) of sea level thrust.

The doomed mission was bound for the International Space Station (ISS) on a flight to bring up some 5000 pounds of (2200 kg) of science experiments, research instruments, crew provisions, spare parts, spacewalk and computer equipment and gear on a critical resupply mission in the Cygnus resupply ship.